Question

Atoms of seven elements a, b, c, d,e, f and g have a different number of electronic shells but have the same number of electrons in thier outermost shells.The elements a and c combine with chlorikeb

Answer 1

1) they belong to 3rd period and groups 1, 2, and 13 - 18 resp.

(A in grp. 1, B in 2, C in 13, D in 14, .... H in 18)

2) ionic compound as one is metallic (B) and the other nonmetallic (F)

this is because B's oxide is basic like metallic oxides and F's is acidic like nonmetallic oxides.

3) A and B as their oxides are metallic.

4) H as it belongs to 18th group which includes noble gases. thus H is most likely to be gaseous.

5) CG3.

C's valency is 3 and G's is 1, therefore by cross multiplication method it can be seen to be C1G3, or CG3.

[A is Na/sodium, B is Mg/magnesium, C is Al/aluminium, D is Si/silicon, E is P/phosphorus, F is S/sulphur, G is Cl/chlorine, H is Ar/argon